1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Simple Silent Alarm

  1. Mar 4, 2006 #1
    I am interested in building a simple silent alarm for a door. All I want to do is set up a system so that a light will blink when the door is opened. I am trying to set this up in a school building for when another teacher enters the room unexpectedly. I'm a TA and it makes it very difficult not to get the teacher in trouble when she keeps coming in and no one notices. Thanks!
  2. jcsd
  3. Mar 5, 2006 #2


    User Avatar
    Science Advisor

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook